[v4] HID:hid-sensor-custom: Fix buffer overrun in device name

On some platforms there are some platform devices created with
invalid names. For example: "HID-SENSOR-INT-020b?.39.auto" instead
of "HID-SENSOR-INT-020b.39.auto"

This string include some invalid characters, hence it will fail to
properly load the driver which will handle this custom sensor. Also
it is a problem for some user space tools, which parses the device
names from ftrace and dmesg.

This is because the string, real_usage, is not NULL terminated and
printed with %s to form device name.

To address this, initialize the real_usage string with 0s.

Reported-and-tested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217169
Fixes: 98c062e82451 ("HID: hid-sensor-custom: Allow more custom iio sensors")
Cc: stable@vger.kernel.org
Suggested-by: Philipp Jungkamp <p.jungkamp@gmx.net>
Signed-off-by: Philipp Jungkamp <p.jungkamp@gmx.net>
Signed-off-by: Todd Brandt <todd.e.brandt@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
Changes in v4:
- add the Fixes line
- add patch version change list
Changes in v3:
- update the changelog
- add proper reviewed/signed/suggested links
Changes in v2:
- update the changelog

 drivers/hid/hid-sensor-custom.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

On Tue, 2023-03-14 at 11:12 -0700, Todd Brandt wrote:
> On some platforms there are some platform devices created with
> invalid names. For example: "HID-SENSOR-INT-020b?.39.auto" instead
> of "HID-SENSOR-INT-020b.39.auto"
> 
> This string include some invalid characters, hence it will fail to
> properly load the driver which will handle this custom sensor. Also
> it is a problem for some user space tools, which parses the device
> names from ftrace and dmesg.
> 
> This is because the string, real_usage, is not NULL terminated and
> printed with %s to form device name.
> 
> To address this, initialize the real_usage string with 0s.
> 
> Reported-and-tested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217169
> Fixes: 98c062e82451 ("HID: hid-sensor-custom: Allow more custom iio
> sensors")
> Cc: stable@vger.kernel.org
> Suggested-by: Philipp Jungkamp <p.jungkamp@gmx.net>
> Signed-off-by: Philipp Jungkamp <p.jungkamp@gmx.net>
> Signed-off-by: Todd Brandt <todd.e.brandt@intel.com>
> Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

> ---
> Changes in v4:
> - add the Fixes line
> - add patch version change list
> Changes in v3:
> - update the changelog
> - add proper reviewed/signed/suggested links
> Changes in v2:
> - update the changelog
> 
>  drivers/hid/hid-sensor-custom.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/hid/hid-sensor-custom.c b/drivers/hid/hid-
> sensor-custom.c
> index 3e3f89e01d81..d85398721659 100644
> --- a/drivers/hid/hid-sensor-custom.c
> +++ b/drivers/hid/hid-sensor-custom.c
> @@ -940,7 +940,7 @@ hid_sensor_register_platform_device(struct
> platform_device *pdev,
>                                     struct hid_sensor_hub_device
> *hsdev,
>                                     const struct
> hid_sensor_custom_match *match)
>  {
> -       char real_usage[HID_SENSOR_USAGE_LENGTH];
> +       char real_usage[HID_SENSOR_USAGE_LENGTH] = { 0 };
>         struct platform_device *custom_pdev;
>         const char *dev_name;
>         char *c;

On Tue, 14 Mar 2023, Todd Brandt wrote:

> On some platforms there are some platform devices created with
> invalid names. For example: "HID-SENSOR-INT-020b?.39.auto" instead
> of "HID-SENSOR-INT-020b.39.auto"
> 
> This string include some invalid characters, hence it will fail to
> properly load the driver which will handle this custom sensor. Also
> it is a problem for some user space tools, which parses the device
> names from ftrace and dmesg.
> 
> This is because the string, real_usage, is not NULL terminated and
> printed with %s to form device name.
> 
> To address this, initialize the real_usage string with 0s.
> 
> Reported-and-tested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217169
> Fixes: 98c062e82451 ("HID: hid-sensor-custom: Allow more custom iio sensors")
> Cc: stable@vger.kernel.org
> Suggested-by: Philipp Jungkamp <p.jungkamp@gmx.net>
> Signed-off-by: Philipp Jungkamp <p.jungkamp@gmx.net>
> Signed-off-by: Todd Brandt <todd.e.brandt@intel.com>
> Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
> Changes in v4:
> - add the Fixes line
> - add patch version change list
> Changes in v3:
> - update the changelog
> - add proper reviewed/signed/suggested links
> Changes in v2:
> - update the changelog

Applied to for-6.3/upstream-fixes, thanks.